Method of and apparatus for venting molds.



I. 0 DAVIS. METHOD OF AND APPARATUS FOR VENTING MOLDS.

7 APPLICATION FILED APR.2Z, I915. LIWQQ EPB Patented Oct. 26, 1915,

,1 2 S'HEETSSHEET i.

WITNESSES: V 4 IN VENTOR.

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J. C. DAVIS.

METHOD OF AND APPARATUS FOR VENTING MOLDS.

APPLlCATlON FlLED APR. 22, 1915.

1 y w, Patented 0ct.26,1915.

2 SHEET$-SHEET 2.

WITNESSES." IN VENTOR.

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" useful Improvements in Methods of and JAMES C. DAVIS, {1F HINSDA E,

" described in the OF NEW YOJRI NEW JERSEY.

METHOD 07: APPARATUS FOR VENTING IVIOLDS.

Application filed April. 22,

To all whom it may concern: I

Be it known that 1, JAMES (J. .DAVIS, a citizen of the United States,andresident of Hinsda-le, in the county ot' Dupage and State ofIllinois, have invented certain new and Apparatus for Venting Molds, 01-which the following is a specifiication.

This invention relates to a novel method of venting molds and has forits object the location of a vent conduit which will be of a certaindefinite size and accurately located at all times with respect to themold cavity and which will further be simple and inexpensive enough towarrant its adoption in general practice.

nder certain conditions of casting steel, due to peculiarcharacteristics of designs, the temperature or composition of the metal,the density and condition of the sand structure in the mold, porosity isencountered on thesurface of the resultant casting. This is especiallytrue where the metal is run into thin sections and where extremesolidity is de sired, such for instance as members which are normallyunder tension when under service loading. The object of my invention isto provide means which will prevent the formation of porosity on thesurface of these important members, especially where the product is aspecialty or the work is duplicate so that it is possible to standardizein the matter of venting. To a large extent solidity i structure can beimluccd by providi .g oil? the 3 conta :ind n: setal in th.-. member ofin eating. it has been :t'o'und that by proper location of the vrnt andby proper graduation in size it is possible to eliminate theobjectionable surface porosity from the re ltant castings.

'lhe preterred form oi my invention is shown on the accompanyingdrawings a nd .pecii'ication but there is no intention to limit theinvention to the precise apparatus shown as considerable modilicationmay be made without departing the scope and spirit thereof. on will bemore fully unde he inven stood by re crcncc to the at ompanyi drawings,wherein, l iguro l. is a plan scctioual view of a mold taken on the lineAA, of Fig. 2 the sand being omitted; Fig. 2 is a cross section taken onthe line Specification of Letters Patent.

Iratented that 26, 1.9115.

1915. Serial No. 23,038.

B-B, of Fig. 1 the sand being shown; Fig. 3 is a perspective view of aportion of the pattern showing the vent rod held in position; Fig. 4 isan enlarged cross section on the line CC of Fig. 1, and Fig. 5 is alongitudinal section on the line DD of Fig. 4.

In the drawings 10, indicates ahalf pattern of metal, mounted on a flatmatch plate design of pattern 10, is shown as simple as possible toclearly illustrate the features of my invention but a pattern of anydesign regardless of complexity may be simi larly adapted and'changed toembody the principles of my invention.

A flask 12, of the usual construction is then placed on the match plateand located with respect to the pattern by means of the flask pins.These flasks are provided with holes 13, which are of size and locationdependent upon the design of duced by the mold.

On the pattern are placed suitable lugs or prints 14; these may befastened on or cast or formed integral with the pattern as desired.These lugs or prints 14-, are provided with draft as clearly shown inFigs. 3 and 4, so that they may be easily drawn from the sand. Theprints are each provided with an aperture 15, to serve as a bearing fora vent rod 16. By this means I am enabled to locate the vent rod inposition with regard to the section of the casting to which they apply.The vent rod is securely held in alinement with the pattern member andthere is no danger of variation in position or i'nisplacolncnt duringthe operation of ramming the mold. This is an important Feature as ithas been found that to get the best results, the vent conduitmust havesome definite relation to the metal section. By the method alreadyexplained, this relation when established is permanent and no variationcan occur as the vent has been so standardized that results can besecured with ordinary unskilled molding labor.

The vent rods lo, are provided with suitable handles 17, so they can bedrawn mamt ally from the tiash at the proper time. The pattern providesa mold cavity 18, in the sand for-tiling the mold and small stop-olfcores 19, are employed to close oil' the rcccsses l'ormcd by prints 14.

The manner oi carrying my invention into practice is as follows: Theflask 12, is placed the casting pro on the match plate so as to surroundthe patsition by means of the usual flask pin arrangement. The vent rods16, are new in sorted through the holes .inthe sides of the flask andare then threaded through apertures 15, in lugs 14, attached to thepattern.

When the vent rods are all in position, the flask is filled With facingand backing-up sand and rammed up. T he vent rods 16, are now drawn outof the mold and the flask lifted oil the pattern or the plate rolledover and the pattern drawn out oi the mold, or stripped. out of thesand, depending on how molding equipment is employed. The mold is nowready for coring and such finishing as necessary. It will'be apparentthat When the pattern is drawn. from the mold there will be impressionsin the sand corresponding to the prints lei, andthese must be stoppedoil" with the cores 19, so that the mold cavity has the requisite shapeand contour as demanded in the finished casting.- These cores 19, beingprovided with a recessed bottom surface :20, do not interrupt thecontinuity of the vent conduit hitherto formed in the sand by the ventrods.

I claim:

1. The method of molding which consists in placing a pattern in a hash,locating venting tool in proximity to and in substantial parallelismwith an edge oi the pattern,

ramming sand around said pattern and between said tooland pattern,removing said pattern and tool, said tool being Withdrawn lengthwise toprovide a vent opening along- "do and substantially parallel with thepattern and out of communication with the casting space, substantiallyas described.

1n apparatus for molding, the combination of flask containing sand, apattern in said flask, and a rod lying alongside and substantiallyparallel to an edge of said pattern, said rod. upon removal beingadapted to provide a vent opening substantially parallel with the edgeof the casting to be formed, substantially as described.

3. In apparatus for molding, the combination of a flask containing sand,a pattern, a. venting tool associated with and located substantiallyparallel to an edge of said pattern and maintained in proper relationthereby, said tool being adapted for removal separately from saidpattern thereby leaving a venting space alongside said casting and outof communication with the casting space, substantially as described.

Signed at Chicago, Illinois, this 16th day April, 1915.

JAMES C. DAVIS.

Witnesse-

